DE602004001600T2 - Commutator segments with contact lug - Google Patents

Description

These The invention relates to commutators or similar rotary switches and in particular Commutator segments used to make same.

background the invention

numerous existing commutators or high-speed rotary switches, which typically used with electric motors, have several copper segments on that arranged to a cylinder and in a non-conductive (often Phenolic) potting compound are anchored. Each segment is from his Neighbor segments physically separated and electrically isolated, so that an electric brush, extending along the outside diameter of the cylinder moves a conductive path only to the segment (or Segments) with which they contact at a given moment stands. The commutators also have flags, so that the ends An anchor can be connected to them.

State of technology

The Document GB-A-2 180 412 discloses "in somewhat larger commutator assemblies, each commutator segment is formed as a bar-like element. A composite riser means formed at one end of the commutator, including a riser serving for each commutator bar. The riser serving has a slot of the commutator, including a riser portion for each commutator bar. The riser portion has a slot formed therein for receiving and holding a coil end "(In slightly larger commutator assemblies Each commutator element is designed as a rod-like element. A composite flag element is at one end of the commutator formed, which contains a flag portion for each Kommutatorsegment. Of the Flag portion has a slot formed therein for receiving and holding a coil end) (page 1, lines 37 to 44).

One Another currently used method of forming commutators involves the cold deformation of a copper rod followed by a ring by forcibly extruding a section of the segment to an elongated one Shape. Different surfaces this preform must then sanded and the preform slotted to a reasonable provide electrical insulation. After that, phenol insulation material potted on the preform to form an insulating core of the resulting To form commutator, and the ring punched to alternate slots and to form flags.

The earlier Training this way of commutators with flags is fraught with many difficulties. Tool-related restrictions such as B. the lack of effective anchoring of rods or Segments of these commutators contribute to the structures fail earlier as desirable is. The inability, the Kommutatorfahnenköpfe with an anchorage for The bars can provide, alike to structural breaks contribute when commutators are made in this way.

The Document FR-A-2504318 discloses a method according to the preamble of claim 1.

Task of invention

It It is an object of the present invention to provide a process for the preparation conductive Segments for Commutators or similar Rotary switch to provide the above problems of complexity overcomes the production and that in one or more embodiments simpler and more effective method for anchoring the commutator segments in provides the nuclei.

Summary the invention

According to the present The invention relates to a method for producing conductive segments for commutators or similar Rotary switch on the steps according to claim 1.

According to one embodiment The method of the present invention is applied to an edge of the Strip one in the longitudinal direction extending guide groove for one Commutator banner provided. The groove can be machined or otherwise processed to form a flag slot made become.

According to the procedure The present invention will be extended longitudinally, periodically notched zones formed in one or both sides of the strip. One or more in the longitudinal direction extending ribs are on one or both sides of the strip and are then machined or otherwise processed, around the longitudinal direction to form extending, periodically bulged zones.

According to one another embodiment of the process of the present invention will be longitudinal extending annular notches in a corresponding end of each strip educated.

In accordance with the present invention, a method of making a commutator or similar rotary switch further comprises assembling the commutator segments made by the method of the present invention to a laterally spaced apart one To form an annular preform with a central opening, as well as the casting of a core in the opening and between the segments.

According to one embodiment This method of the present invention becomes a reinforcing ring into or into each annular groove formed by the annular notches the casting the core fitted.

Other Objects, features and advantages of the present invention are exemplified in the following description and the drawings or shown.

Brief description of the drawings

1 Figure 11 is a perspective view of a base strip of the present invention.

2 is a view of an elongated version of the base strip of 1 showing strip blanks to be cut from it.

3 is a perspective view of one of a strip blank of 2 formed segment.

4A to B are perspective views of a multiple segment preform of FIG 3 represented type.

5 is a perspective partially cutaway view of the in the 4A to B shown preform with an insulating core formed therein.

6 is a perspective partially cutaway view of the preform and the core of 5 after drilling and turning.

7 is a perspective partially cutaway view of the preform and the core of 6 in the slotted state to form an exemplary flag commutator.

8th Figure 4 is a perspective view of an alternative base strip of the present invention.

9 is an end view of the base strip of 8th ,

10 is a perspective view of one of the base strip of 8th formed segment.

11 is a partial sectional view of a multiple segment preform of FIG 10 represented type.

12 is a perspective view of a flag commutator from the preform of 11 ,

detailed description

The 1 to 2 show an embodiment of the base strip 10 of the present invention. As can be seen, the strip is 10 an elongated strip of suitable electrically conductive material such as copper and has 1 a generally Y-shaped cross section; the strip is preferably formed by means of a corresponding die-forming process. The stripe 10 is cut into strip blanks, from which commutator segments 14 ( 3 ) are formed.

Along the upper edge 18 of the strip 10 is a long groove 22 which serves as a commutator tab guide to facilitate the formation of slots between the tabs in which anchor wires can be connected. Alternatively, the groove 22 be preformed to the finished depth of such slots, so that no further machining of the strip 10 is required.

The pages 26 and 30 of the strip 10 include laterally projecting longitudinally extending ribs 34A respectively. 34B , As in 2 can represent periodic lengths of the rib 34B embossed (or otherwise compressed, pressed or removed) to longitudinally extending periodically bulging zones 38B on the strip side 30 (see. 3 ) between the rib sections. The rib 34A can be similarly machined to longitudinally extending periodically bulged zones 38A in the strip side 26 to build. In their entirety, these bulging areas contribute to adjacent segments 14 Insulate electrically in a finished commutator as they prevent adjacent segments 14 come into contact in these zones. The strip blanks 14 could also be formed with longitudinally extending periodically bulging zones on one side only. The longitudinally extending periodically bulged zones 38A and 38B can be formed in any other suitable manner, including the construction of ribs 34A and 34B on the corresponding pages 26 and 30 by adding instead of removing or moving material.

The lower edge section 42 of the strip 10 has longitudinally extending grooves 46A and 46B in every page 26 . 30 that eventually contribute to the segments 14 to anchor in an insulating core of a commutator.

The version of the in the 1 to 2 is set strip 10 also shows laterally projecting longitudinally extending ribs 50A and 50B , where the shoulder 50A between the rib 34A and the groove 46A and the shoulder 50B between the rib 34B and the groove 46B is positioned. However, as will be discussed later, other embodiments of the strip are omitted 10 such shoulders 50A and 50B ,

In accordance with the 2 to 3 can the strip blanks 14 punched, sheared or otherwise individually from the strip 10 be formed. This in 3 illustrated finished segment 14 contains an integral commutator flag head 54 and a segment 58 one of which is disposed substantially perpendicular to the other. The head 54 and the segment 58 need not necessarily be perpendicular to each other, although this (or substantially perpendicular) can often be useful. The lower edge of the segment 58 has an inverted T-shaped anchorage 70 that is between the bottom edge 42 and the long grooves 46A . 46B is trained.

In the 2 to 3 are longitudinally extending annular notches 62 and 66 in each end of the segment 58 which are preferably (but not necessarily) generated when each segment 14 is formed, such as by periodic cutting, punching or otherwise material removal from the lower edge 42 of the strip including the long grooves 46A . 46B , Each of the ring notches 62 and 66 is designed to receive a reinforcing ring to improve the stability of the resulting commutator. However, the use of such reinforcing rings is optional, and one or both of the ring notches 62 and 66 can be omitted if desired.

Although in 2 not shown, shows 3 a longitudinal slot 70 , the segment anchorage 74 into the anchorages 74A and 74B Splits. As will be disclosed later herein, the anchors 74A and 74B wholly or partly embedded in the core of the resulting commutator to improve stability. If provided, the anchoring slot 70 preferably (although not necessarily) produced when each segment 14 from the strip 10 is formed.

The 4A to B show sets of segments 14 spaced side by side in an annular preform 78 with a central opening 94 assembled. Optional reinforcement rings 82 and 86 are each in the of the ring notches 62 and 66 the assembled segments 14 fitted ring grooves formed. Unless they are used, the rings can 82 and 86 both temporarily (to maintain the assembly of the segments 14 to the preform 78 ) as well as permanently (to improve the stability of the resulting commutator) are used.

The core 90 ( 5 ) can then in the opening 94 the preform 78 between the segments 14 to be shed. The core 90 typically consists of an electrically insulating material such as a phenolic resin and is made by conventional molding techniques such as injection molding. The consequence of the forming operation is an assembly 98 in which both the segments 14 as well as the rings 82 and 86 the preform 78 embedded and thereby in the material of the core 90 are anchored.

6 specifically shows the anchoring of the segments 14 , being material of the core 90 with inserted slots 70 between the anchorages 74A and 74B is shown. Also shows 6 a hole 102 centrally through the assembly 98 runs and facilitates the installation of the finished commutator on a shaft for use.

Finally shows 7 an example of a finished commutator 106 , To the commutator 106 from the assembly 98 Width and depth of the guides will be established 22 enlarged to flag slots 110 between the flags 114 to build. The anchor wires can then slot with the selected tabs 110 fused or otherwise connected. The segments 58 can be slotted axially to enhance their physical separation and improve electrical insulation.

The 8th to 9 show an alternative strip 10 ' , The stripe 10 ' is the strip 10 essentially similar and has like 9 can be seen a generally Y-shaped cross-section. Unlike the strip 10 but has the strip 10 ' the upper edge portion has longitudinally extending grooves 118A and 118B in the pages 26 ' respectively. 30 ' , which are intended for the formation of flags head notches. How out 12 can be seen, the flag head scores 118A to B with the material of the core 90 are filled, whereby a further anchoring of the heads of the respective segments is achieved. Notches or other anchoring means may be on or in areas of the strip 10 ' be arranged by the sides 26 ' and 30 ' are different. 10 shows a segment 14 ' that's from the strip 10 ' was made while 11 a preform 78 ' shows, which consists of several segments 14 ' assembled.

The advantages of the present invention arise not only from the finished commutators, but also from the starting materials and the processes by which they are made. By using a strip from the Base material, for example, a rod, it is possible to provide the strip with the many useful features described above. The formation of individual segments by shearing (rather than, for example, by coextrusion, followed by slitting the result for electrical insulation) also allows for the formation of anchoring means such as e.g. B. the flag head scores 118A or 118B especially for the head of each segment. The shearing off of the segments also allows the use of reinforcing rings with flag commutators, which is not conventional, and allows the support of electrical insulation by embossing ribs of the base strips. In addition, the present invention avoids the need to extrude metallic materials or grind their surfaces.

by virtue of surpass these innovative concepts exemplary commutators of the present invention commercial Products in many ways. For example, some embodiments have the present invention a via 25% improvement in spin resistance compared to existing ones commercial Flag commutators shown. Other tests are similar Suggest that the segment separation force of commutators of the present invention is about three times higher than that for separating the segments of the existing conventional product required is. Furthermore, the depth of wear of Commutators of the present invention by about one-third greater than that of the existing commercial one Product.

Claims (8)

A method of manufacturing conductive segments for commutator rotary switches or the like, comprising the steps of: I) providing an elongate strip ( 10 ; 10 ' ) of a material having a given cross-sectional profile ( 34 . 46 . 50 ; 34 ' . 46 ' . 118 ); II) cutting or otherwise cutting the strip to blanks ( 14 ; 14 ' ) to build; and III) machining or otherwise processing each blank ( 14 ; 14 ' ) to a segment ( 58 ; 58 ' ) with a protruding commutator flag ( 54 ; 54 ' ); characterized by the steps of: IV) forming one or more laterally projecting longitudinally extending ribs (Fig. 34A . 34B ) on one or both sides ( 26 . 30 ) of the strip ( 10 ); and V) machining or otherwise processing periodic lengths of the rib to provide longitudinally extending periodically bulged zones (US Pat. 38A . 38B ) to help create adjacent segments ( 14 ) in a finished commutator electrically isolate. The method of claim 1 and further characterized by the step of providing one or more longitudinally extending grooves ( 46A . 46B ; 118A . 118B ) in one or both sides ( 26 . 30 ; 26 ' . 30 ' ) of the strip ( 10 ; 10 ' ). A method according to claim 1 or 2 and further characterized by the step of forming a longitudinally extending notch ( 62 . 66 ) in a corresponding end of each strip ( 10 ). Method according to one of claims 1 to 3 and further characterized by the step of providing longitudinally extending grooves ( 70 ) in each side of the other edge portion ( 42 ) of the strip ( 10 ) to a segment anchor ( 74 ) define. The method of claim 4 and further characterized by the step of periodically machining or otherwise notching the other edge portion (10). 42 ) at the side of the strip to anchor ( 74A . 74B ) train. A method of manufacturing conductive segments for commutator rotary switches or the like, comprising the steps of: I) producing conductive segments according to the method of any one of claims 1 to 5; II) Assembling the commutator segments ( 14 ; 14 ' ) spaced side by side to an annular preform ( 78 ; 78 ' ) with a central opening ( 94 ); and III) forms of a nucleus ( 90 ) in the opening and between the segments, wherein the contact between adjacent segments through the zones ( 38A . 38B ) is prevented. The method of claim 6 and further characterized by the steps of: I) producing conductive segments according to the method of any one of claims 3 to 5; and II) fitting a reinforcing ring ( 82 . 86 ) in the or each of the annular grooves through the ring notches ( 62 . 66 ) are formed before forming the core ( 90 ). A method according to claim 6 or 7 and further characterized by the step of forming the core ( 90 ) with a bore ( 102 ).